This invention relates to coal solubilisation.
Coal solubilisation involves extracting organic material from the coal into a solvent and filtering the organic-rich solvent to remove the undissolved organic and mineral matter. Various coal solubilisation methods are known. One such method involves contacting the coal with hot, e.g. about 200.degree. C., N-methyl pyrrolidone (NMP). This method achieves approximately 50% dissolution of the organic material and must be carried out at elevated temperature. Coal can also be solubilised in a mixture of NMP and carbon disulphide at room temperature. However, this dissolution medium is extremely odorous and unpleasant. Also, the products produced tend to be sticky and rather difficult to work with and contain an undesirable amount of sulphur.